Six key moments from NASA's 60-year history

The Soviet Union launched its Sputnik satellite in 1957, beating US to the punch and prompting fears of Soviet dominance in space. In January of the next year, the US army responded by sending up the Explorer 1 satellite (pictured above). And on July 29, 1958, the US Congress approved the creation of the National Aeronautics and Space Agency, or NASA. The agency opened its doors on October 1.

NASA managed to land humans on the surface of the moon on July 20, 1969, just 11 years after the association's foundation. The feat was accomplished using less computing power than that possessed by the modern-day smartphone. The photo shows Neil Armstrong and Erwin Aldrin planting the US flag on the lunar surface.

On April 14, 1970, an oxygen tank on the Apollo 13 spacecraft exploded, prompting astronaut James Lovell (center) to report back to NASA base in Texas: "Houston, we've had a problem." The crew made it back to Earth after a risky repair operation. Lovell's phrase, slightly misquoted, was made famous by a 1995 movie, Apollo 13.

The Challenger Space Shuttle was not as fortunate as Apollo 13. It exploded, killing all seven people on board, just minutes after takeoff on January 28, 1986. Famed physicist Richard Feynman eventually determined that the crash was caused by a rubber seal ring that failed in unusually cold temperatures.

The Cold War rivalries between Russian and American scientists were finally buried on December 14, 1998, when the US-built Unity module and the Russian-made Zarya module docked in space. The two modules form the basis of what we now know as the International Space Station (ISS).

On August 6, 2012, NASA landed the Curiosity rover on the surface of Mars. The mobile laboratory is still sending scientific findings, selfies and even tweets from Mars, albeit with a little help from its Earth-based handlers. Curiosity's data is crucial for NASA's next mission: landing humans on Mars some time in the 2030s.